Current source arrangements serve for example to supply one or more electrical loads with electrical power. In this case, it is possible to provide for example a plurality of series circuits, comprising a respective current source and a respective assigned load. If the branches connected in parallel in this way are supplied with a common supply voltage, then it may be desirable to regulate the supply voltage. In this case, by way of example, the voltage dropped across each current sink can be measured and the minimum one of the current sink voltages can then be determined. This lowest current sink voltage is compared with a setpoint value and the supply voltage is varied in a manner dependent on the comparison result. This ensures that the minimum voltage dropped across the current sinks corresponds at least to the threshold value. As a result, all the current sources operate in a predetermined voltage range.